Gripper



June 16, 1925.

c. F. PYM

GRIPPER original Filed Feb. 1, 1917 Patented June 16, 1925e UNITED-STATES PATENT OFFICE.

ommnns r. PYM, or LYNN, nessncnusnrrs; Assrenon T0 UNITED SHOE MAGHIN- nnYconronA'rIoN, o1" rarnnson, new atessnv, a CORPORATION or new JERSEY.

j enrrrne.

Original. application filed llfebruar'y 1 1917, Serial No. 146,028. Divided. and this application filed i i November 12, 1920- 'fierial No. 423,538,

To all wlaomz't may conctrn: it

Beit known that I, GrIAnLEs F. PYM, a subject of the King of England, residing at Lynn, in the county of Essex and State of: Massachusetts, have invented certain Im- PJTOVQII'IBDtS in Grippers, of which the following description, in connection with the accompanying drawings,-is a specification, like reference characters on the drawings indica-tin like parts in theseveral figures.

This invention relates to grippers or pince-rs for use in machines for working uppers over lasts. While the ,form of gripper herein shown and described for the purpose r of exemplification is of, special utility in 'machines of the type disclosed in United States Letters Patent. No. 1,418,613, granted April 25,1922, on my application, of which the presentapplication is a division, it is to be understood that the'i'nvention is of generalutility in machines requiring a gripper or grippers for working an upper over a lastsuch, for example, as pulling-over machines and hand methodlasting n'ia-chines.

A general object of the invention is to provide an improved gripper mechanism which is simple and rugged in construction i and which will not only hold the stock prcsented between the jaws securely but which has a movable. jaw which reaches out and gather-sin the stock.

In presentii'ig shoe uppers to machines in which gripper or pincer grasps the upper material and stretches it, it is notonly desirable that the shoe upper may beeasily positioned to cooperate with the gripper, that is, that the gripper jawsopen widely, but it is also desirable that the movable jaw of the gripper, in closing upon the stock, shall gather in all of the upper material within its reach against the fixed jaw. A feature of the present invention consists, therefore, in a novel gripper mechanism in cluding a gripper jaw having an out-reaclr v ing component of movement at the beginning of its closing movement which changes to an inwardcomponent toward the end of the closing moven'ient, so that the moval'ile jaw reaches out over the presented upper n iaterials and then gathers them in toward and against the fixedjaw of the gripper.

This and other features of the invention will appear more fully from the following description of the mechanism in which the invention is embodied, when read in connec tion with the accompanying drawing, and will be pointed out in the appended claims The figure of the drawing is a vertical section on a large scale of a gripper mechanism einliiodying this invention.

The gripper comprises a lower or relatively stationary jaw 6, the gripping face of which slopes upwardly and outwardly relatively to the margin of the upper presented to it and has at its outer end an up standing shank portion 8 which is rigidly secured to an operating member 4: which is given, by cams or otherwise, movements to effect the updrawing, overdrawing or other movements usually imparted to the gripper in m-achines of this class. Preferably, for convenience in assembling, the aw portion 6 is-formed separately from the shank portion 8 and is rigidly secured thereto by a plurality of machine screws or other suitable securing means.

The shank 8 is formed with a vertical bore extending upwardly through its upper end and, below the bore, is channeled vertically and downwardly to its lower end to form an elongated slot 10 within the lower end otwhich the jaw portion 6 is seated and secured. i

A reciprocating plunger 12 works in the vertical bore of. the shank 8 and extends downwardly into the slot 10, its lower end having a lateral offset 14 projecting outwardly through the slot 10 and pivot-ally connected at 15 to the upper end of the shank portion of a movable gripper jaw 16. The jaw16, between its ends, is pivotally supported from the fixed jaw by a link 18 which is of greater length than the offset 14; and is pivotally connected to the movable and fixed jawsrespectively at points 17, 19 which are at different distances from their lower extremities with the pivot point of the link on the fixed jaw substantially removed rearwardly from vertical alinement with the point of pivotal connection of the offset 14- tothe movable jaw 16. In raised position of the plunger 12 the link 18 is inclined upwardly from the-horizontal so that downward closing movement of the movable jaw 18 will include successive components of outward and inward movement.

On downward movement oi the plunger 12, the offset 1&- and link 18 will cause .the jaw 16 to move downwardly and coincidcntly to swing the gripping end of the jaw at first outwardly until the link pivot-s are horizontally alined and then, as the outer pivot 01 the link passes below the plane horizontal alinement of the pivots, to swing the gripping end of the movable jaw ab rupt'ly inwardly. the inward component of movement supplanting the outward component toward the end of the closing movement so that the path of movement forms a hook-lil e curve with a sharp inward bend of the hook at the end of the movement. This action causes the jaw 16 to reach out and gather in the lining and the upper and to draw them toward and clamp them against the fixed jaw, the link being then substantially parallel to the gripping faces of the aws and the clamping force being applied substantially normal to the grip iiing plane. It will be apparent that the central portion of the jaw member 16 moves in a circular path on the link 18 as a radius while its upper end is constrained to move in a rectilinear path which lies in an extended chord of the circular path of the central portion, since the pivot 15 is located laterally between the ends ot the link 18.

The gripping face of the fixed jaw is preferably inclined at substantially 45 degrees to the horizontal so that when the shoe is presented, for example, with its sole upward and in a substantially horizontal plane, the upper, in its usual outwardly flared position, will readily enter between the jaws which will then be at rest and widely opened. Shoe positioning devices any usual or desired construction may be provided to locate the shoe relatively to the gripper.

The closing of the gripper is effected by movement of an operating member 20 relatively to the member a which may be caused to-take place by cam mechanism such as that disclosed in the parent application above referred to or otherwise. T he upper end 01 the plunger 12 is pivotally connected by a pin 22 to the lower end of a link 24-, the upper end of which is pivotally connected by a pin 26 to the lower end of a push rod 28 the pin 26 being arranged at right angles to thepin so that substantially universal movement of the gripper and its operating member 4- relatively to the member 20 may take place in a horizontalplane. Closing of the gripper is eflected yieldingly by downward vertical movement of the member 20 relatively to the member l. To effect this a bearing member 30 is loosely mounted on the rod 28 and between the member and a nut threaded on the rod 28 is arranged a spring 34. The upper end of the bearing member is spherically formed to engage a corresponding recess in the member 20 to provide a ball and socket joint. The rod 28 above the nut 32 is reduced and extends through the bearing member 30 and through the operating member 20 which is coned out above .the spherical seat of the bearing member 30 to permit play of the upper end of the rod. An adjustable collar 36 is secured by a set screw to the upper end of the rod 28 and bears against the upper face of the member 20 to hold the rod 28 against downward movement relatively to the member while the spring 34 permits relative yielding movement between the member 20 and the closing rod 28 so that when the member 20 is moved downwardly the upper material is gripped yieldingly by the gripper which will yield in the upper pulling movement of the gripper to prevent tearing of the upper. Obviously the tension of the spring '34-, and hence the yielding point of the gripper jaws may be varied by adjusting the nut 32 on the rod 28.

It will be seen that, because of the universal connection 30 between the push rod 28 and its operating member 20, and the universal connection comprising the pivots 22, 26 between the push rod and the movable jaw 16 the relatively fixed jaw member 8, and, of course, the movable jaw, may be moved transversely as well as longitudinally in any desired direction by the operating member 4 to effect the manipulation of the upper.

It is to be understood that ,the term fixed jaw as used in the description refers to the jaw relatively to which the other aw moves in closing upon the stock, both jaws being then moved to manipulate the stock, and also that, although the gripper mechanism has been described and defined in some of the claims as vertically arranged, such a position has been assumed for convenience merely, the position of the gripper being readily variable to meet the requirements of the machine in which it is employed.

Having thus described my invention, what I ,clahn as new and desire to secure by Letters Patent ot the United States is:

l. A gripper mechanism comprising a fixed lower jaw having an upwardly extend ing shank. an operating plunger guided in and extending upwardly of said shank and having an outwardly offset lower end, an upper movable jaw having a shank portion pivotally connected at its upper end to the offset lower end of said plunger, a link having its rear end pivotally attached to the lower fixed jaw at a point rearwardly ol the pivot point on said. oiiset end and having its forward end pivoted to said movable jaw at a pointintermediate of its ends, and means for reciprocating said plunger to move said upper jaw toward and from the lower fixed llH to co-operate with said link in swinging the jaw portion of its connected shank toward and from the other jaw.

3. A gripper mechanism comprising relatively movable gripping jaws each provided with a shank portion, a link connecting the shank portions of said jaws at different dis tances from the ends of their respective grippingportions, and an operating member directly connected to the shank portion of one of said jaws and movable in a right line direction to cause said link to act to swing said jaw toward and from the other jaw.

4. A gripper mechanism comprising relativel movable gripper jaws provided with shanc portions extending in the same general direction, a single link connecting said shank portions intermediately of their ends at difierent distances from the extremities of said aws; and an operating member having direct pivotal connection with the end of the shank portion of one of said jaws and guided for rectilinear operating movement to swing said jaw toward and from the other jaw.

5. A gripper mechanism comprising a fixed jaw member having a hollow shank, plunger passing through the hollow shank and having an ofiset, a movable jaw member pivoted to the offset, and a link pivoted to the movable jaw member at one end and to the fixed aw member at the other end.

6. A gripper mechanism comprising a fixed jaw member having a hollow shank, a plunger passing through the hollow shank and having an offset, a movable jaw member pivoted to the offset, and a link pivoted to the movable jaw member at one end and to the fixed jaw member at the other end, the pivots of said link being arranged to cause the link to be upwardly inclined when the jaws are open and downwardly inclined when they are closed.

7. A gripper mechanism comprising a fixed jaw member having a hollow shank, a plunger passing through the hollow shank, a movable jaw member pivoted to the plunger, and a link pivoted to the movable jaw member at one end and to the fixed aw member at the other end, said link being arranged to give the movable jaw during closing first a reaching-out movement and then a gathering-in movement as it approaches the fixed jaw.

8. A gripper mechanism comprising a fixed jaw member and a movable jaw member, means to cause one end of the movable jaw member to travel in a rectilinear path, and means for causing outward and inward components of movement to be imparted to the movable jaw during closing.

9. A gripper mechanism comprising a fixed jaw having a gripping face inclined at substantially forty-five degrees to the hori- Zontal, a movable jaw member having an inclined gripping face to cooperate with the gripping face of the fixed jaw and having its opposite end constrained to move in a rectilinear vertical path, and a link connected to the movable jaw between its ends and to the fixed jaw member, said link being arranged to lie substantially parallel to the gripping faces of the jaws when they are in closed position.

10. A gripper mechanism comprising a fixed jaw, a movable jaw member having a gripping face at one end, means for causing a substantially central portion of the jaw memberto move in a circular path, and oper-' ating means connectedto the other end of said jaw member and constraining said end to move in a path formed by the extension of a chord of the circle in which the central portion moves.

11. A gripper mechanism comprising an oblique fixed jaw, a straight movable jaw member having an oblique end face to cooperate with the fixed jaw to seize the work, means attached to the other end of the mov able jaw for eii'ecting movement of said end in a straight line, and means for causing portion of said member between its ends to move in a circular path.

12. A gripper mechanism comprising relatively movable jaws, a pusl1-rod for operating the jaws, operating means for the push-rod, means for effecting bodily longik tudinal and transverse movement of the jaws relatively to the push-rod, operating means, and connections between the puslr rod and its operating means and between the push-rod and the jaws to permit said movements of the jaws.

13. A gripper mechanism comprising a relatively fixed aw member movable longitudinally and transversely to manipulate an upper, a relatively movable jaw cooperating with thefixed jaw, a puslrrod, an operating member for the push-rod, and universal connections between the push-rod and its operating member and between the pushrod and the movable jaw.

In testimony whereof I have signed my name to this specification.

CHARLES F. PYM. 

